Style creation products such as hair styling mousses provide human hair with a temporary set which can be removed by water or by shampooing, and function by applying a thin film of a resin or gum onto the hair to adhere adjacent hairs together so that they retain the particular shape or configuration at the time of application.
Conventional hair styling mousses typically utilise a hair setting polymer, water, surfactant and propellant gas, with optional adjuvants such as aesthetic agents, fragrance and hair conditioning agents. The conditioning agents used have included silicone-type materials.
EP 0 523 388 discloses an aqueous hair styling aid or mousse composition incorporating a non-volatile silicone compound or other water-insoluble, emulsifiable conditioning agent. The preferred non-volatile silicone compound is a 3:1 mixture of a low molecular weight polydimethylsiloxane fluid and a higher molecular weight polydimethylsiloxane gum.
EP 0 205 306 discloses the use of high molecular weight silicone materials in styling mousses. These are defined as polydiorganosiloxanes having a viscosity of at least 100,000 cSt. The high molecular weight silicone is dissolved in the propellant phase prior to filling the aerosol container.
EP-A-240 350 and U.S. Pat. No. 4,902,499 disclose the use of specific rigid silicone polymers dissolved in a volatile carrier material for giving improved style retention to hair. Silicone elastomers are described which are incorporated in the form of an aqueous silicone emulsion comprising an anionically stabilised hydroxylated polyorganosiloxane, colloidal silica and a catalyst, which crosslinks to form an elastomer on the hair when the water content dries out. Also mentioned are highly cross-linked silicone resins and cross-linked siloxanes which are soluble in solvents such as cyclomethicone.
The present inventors have found that an emulsion polymerised silicone material having a particular, defined level of cross-linking, and which is cross-linked in emulsion form can be incorporated into a hair styling composition, such as a mousse, gel or cream, to give a formulation which delivers excellent style creation and longevity, whilst leaving the hair soft and natural.
Unexpectedly these improved properties have been found to be dependent on the presence of the particular cross-linked silicone and its phase behaviour in the formulated styling composition.